1. Field of the Invention
This invention relates to a solar-cell module, and more particularly to a solar-cell module whose reinforcing sheet has been bent, a process for its production, a method for its installation, and an electricity generation system making use of the solar-cell module.
2. Related Background Art
Solar cells have widely been used as clean and inexhaustible energy supply sources, and various research and development has been made in this area. In addition, development is energetically made on solar-cell modules well adapted to be installed on the ground, the roof and so forth.
Such solar-cell modules have begun to be used for various purposes, and with each situation, there are various demands.
One such demand is a solar-cell module making use of a back reinforcing sheet on the back of a solar-cell module. This back reinforcing sheet is bent or perforated so that the solar-cell module can be attached by utilizing the bent or perforated part.
As an example thereof, there is a solar-cell module employing a metallic reinforcing sheet as the back reinforcing sheet, which back reinforcing sheet is bent so that the solar-cell module may be more adaptable than ever to the installation of metallic roof materials.
As an example of this solar-cell module, a technique disclosed in Japanese Patent Application Laid-Open No. 5-121773 is known in the art. This solar-cell module has a metallic reinforcing sheet on the back of the light-receiving side. A photovoltaic device is mounted at the middle of this reinforcing sheet, the photovoltaic device is sealed with a covering material transparent resin, and the metallic reinforcing sheet is bent at its uncovered outer sides (bent portions are not covered with the covering material) so that the bent portions can be utilized to fix the solar-cell module upon installation.
Such a solar-cell module, however, has had a problem that the covering material tends to come off. In such a case, the covering material begins to come off from the margin and may gradually further come off until it comes off at its part directly sealing the photovoltaic device. If this occurs, the photovoltaic device may become detached from the reinforcing sheet and may become greatly damaged, resulting in a great lowering of electrical performance in some cases. Also, even if the covering material does not come off to the extent that the photovoltaic device becomes detached from the reinforcing sheet, water may enter the structure and contact the photovoltaic device to cause a great lowering of electrical performance. Thus, it is a great problem that the covering material comes off as stated above.
Under existing circumstances, however, no solar-cell module has been developed in which the covering material is peel-resistant and the photovoltaic device is protected from damage.